From Conducting Hydrogel to Semiconducting Hydrogel

Thin-film semiconductor-based devices have revolutionized the field of microelectronics. Conducting hydrogels have rapidly gained prominence for bioelectronic applications due to their great similarities with biological systems. The realization of semiconducting hydrogel materials holds significant value in advancing bioelectronics for developing advanced biologics[1]. Further moving towards flexible and stretchable semiconducting hydrogels can enable direct applications at the interface of soft biological systems [1]. However, the development of semiconducting hydrogels presents material challenges, primarily due to the thin-film nature of semiconductors. In contrast, hydrogels tend to have greater thicknesses and struggle to achieve good semiconductor properties.<br/><br/>The advent of organic electrochemical transistors (OECTs) has introduced a new paradigm that can be a powerful testbed to evaluate the performance of a semiconducting hydrogel. In this report, we will trace back the history of the development of the semiconducting hydrogel and its first use in the development of transistors (OECTs) [2]. Moreover, we provide our insight on how to define a semiconducting hydrogel when using OECT as a testbed. Finally, we delve into the development of stretchable semiconducting hydrogels [2] and explore how they can revolutionize applications for tissue-compatible biomedical research.<br/><br/>[1]. Zhang., Shiming, et al. Advanced Materials 32.1 (2020): 1904752.[2]. Liu, Dingyao., Wang, Yan., Zhang, Shiming., et al. Submitted.